Since the BLUETOOTH® headset is portable, people are happy to use it in various occasions, in particular, when they are in sports, they can listen to music and receive calls through BLUETOOTH® headsets, thus bringing great convenience to people in the sports process. So the requirements for the performance and appearance of BLUETOOTH® headsets are increasing. In order to increase the competitiveness of products, manufacturers have introduced BLUETOOTH® headsets of small size and metal housing to improve their portability and appearance, and attract more consumers.
The reduction in size and the addition of metal housing will inevitably increase the difficulty of antenna design. If the existing antenna designs, such as monopole antennas, IFA antennas, and loop antennas, are still used, the antenna performance may not meet the requirements and due to the strong vibration during exercise, the existing antenna design structure is not rigid and it is easily subject to vibrations and is deformed or even broken resulting in poor antenna performance. In addition, in the prior art, the antenna design adopts an independent antenna unit. Although its versatility is good, a certain clearance area is required to occupy a certain space in the headset, the cost is high, and the radiation efficiency of the antenna is low, which is not suitable for application on the in-ear BLUETOOTH® headset.
For this reason, it is necessary to research an antenna that is smaller in size, lower in cost, and is widely used in in-ear BLUETOOTH® headsets.